We've spent hours wandering along beaches picking up unusual objects washed ashore. Rather than storing and forgetting about our finds we make use of them. Bits of tide-washed driftwood and twisted metal become art when placed among the geraniums in our flower-tubs. Surf-smoothed coloured sea glass is ideal for candle-dish decoration. Colourful odds and ends of rope and fishing net floats give a nautical twist to our patio. The children put their collection of shells on our gravelled front garden, making an instant beach, which earned compliments from passersby.

Our London walks along the Thames at low tide have resulted in a fledgling collection of 18th and 19th-century clay-pipe fragments. (Wear wellies and old clothes, it can be muddy.) Though broken, these milk-white objects are surprisingly delicate and one lucky pipe find included a decorated bowl in the shape of a lady's head. When displayed on a patch of velvet, they really stand out and our girls love describing how each was found, speculating over who may have used them.

Readers may find other themes running through their flotsam and jetsam finds. Do your bit for the environment, too, by collecting objects such as plastic bottles and wire, that can injure or kill marine life. Bob Barton

Enrol at knight school

Conventional school is out for holidays but your kids can swap their pens and pencils for swords and shields to enrol for an altogether different kind of learning at knight school this summer. They can step back in time, don some armour and take sword-fighting lessons before participating in a mock battle. And where better to hold a knight school than in a castle?

Thanks to the good eggs at English Heritage, the art of chivalry and honour will be taught at various castles across the country during the summer break, including Bolsover, Kenilworth and Framlingham. The first opportunity to swear allegiance comes this weekend at Beeston castle, where would-be warriors will be assisted by professional reenactors with experience of accurate historical interpretation - common to all knight schools. Antony Jones

· Various dates and English Heritage castle venues. Prices from £4 to £6 adults; £2-£3.50 children. For further information, visit english-heritage.org.uk

Create a bug hotel

With hindsight, things were destined to go awry between Sid and Nancy. But how could we have guessed that when we first happened upon the idea of the bug hotel? Humid summers are creating an exploding insect population in even the most manicured outdoor space. Prey to Darwinian forces, insects have it tough.

The observation hit Lily one balmy Saturday morning as we watched a blackbird winkling a fleshy snail from its shell. Bugs deserve a break. We would create a five-star escape: the bug hotel. Taking a large Tupperware box we pierced air holes in the lid. Then we passed an hour poking around the park, among tree roots, punching down though mulchy stacks of leaves. We selected a snail (Tommy), a ladybird (Lucinda), and two woodlice - named Sid and Nancy after they proved themselves to be 24-hour party insects and repeatedly trashed the "room". Using a botanical encyclopaedia, we collected plants to create the right ambience: bright sweet william nestling among dark evergreens. We ran the hotel like a high-class biosphere, monitoring the air supply (flapping the Tupperware lid), simulating rain drops and replenishing the foliage daily. We had great fun, wrote the experience up for literacy homework and took the bug hotel into Show and Tell. The only smirch on an otherwise rose-tinted experience occurred on the day of checkout when we discovered Nancy's inert body beneath a dock leaf - and a disoriented Sid. The truth about what really happened that night will remain a mystery. Joanne Mallabar

Go to the wall

The powerful Roman Emperor Hadrian might not be too pleased if he knew that we think of him primarily as the builder of a wall! He was a highly successful Emperor, military commander and man of culture. His life and legacy is explored in an amazing new exhibition at the British Museum - with free family trail and activities - which has just opened. "Hadrian: Empire and Conflict" will display 180 objects found all over Hadrian's empire including items newly excavated from his villa near Rome, a huge head and sandaled foot from a 5m statue of the Emperor unearthed last year in modern-day Turkey and, from the BM's own collection, a couple of the fascinating Vindolanda tablets - Roman postcards found near Hadrian's Wall.

The wall is, of course, not just a wall, but a collection of Roman military camps, once like small towns. And they are fantastic to visit. Most sites offer activities for children and there are almost no restrictions: you can wander, climb, explore and be part of the Roman world. See the changing room lockers of the bath house at Chesters or sit on Roman loos where soldiers sat together and chatted. Juliet Rix